Flame arrester



July 11, 1950 v s, s 2,514,823

FLAME ARRESTER Filed April 25, 1948 v l/v vE/vToe l 4 SAMUEL H. Yos-r,

HTT'Y,

Patented July 11, 1950 EFF- ri wm ss' i sSarhueI-"H.-f$0513}Worthington;i-()hio,assignoi -td i I The.leifreyzManufacturing Company, acorporation of Ohio {applicationAmines, ierajsensino.22.932

This-invention relates to a flame arrester, and an object of theinvention. is to provide a very simple improved device of the abovementioned typeiii T, i I

Other objects of the invention:willrappear4hereinafter, thenovelrfeatures and combinations being set forth in theappended claim.

In the accompanying drawing:

Fig. I is; an elevational rviewlof a controller to which a pair of myimproved flame arresters have been attached} and Fig .2;is a detailedview,-,part in section. and part in: plan, showing the constructionofsaid am a r ste i i Flame arresters are required in permissibleequipment to prevent explosions when said equipment is used in gaseouscoal mines. In connection with controllers or other spark producingequipment used with coal mining machines it is desirable to maintain aflow of air through the enclosed casing at all times so that the ionizedair produced whenever a contact is open will not form sufficient nitrousacid which is allowed to form will seriously attack the copper,insulation and, in fact, many operating parts of the controller.

As illustrated in Fig. -1 of the drawings, the controller I is providedwith a pair of flame arresters ll of similar construction, one of whichis connected to a flexible conduit l2 which derives a flow of air from afan or blower, the air flowing through the flame arrester II and intothe totally enclosed housing of the controller I'll, thence out of saidhousing through the other flame arrester I l at the left-hand side ofsaid controller, as viewed in Fig. 1 of the drawing.

The flame arrester of my invention is very simple,,yet it has been foundentirely satisfactory and has been approved by the Bureau of Mines. Itcomprises essentially two main parts. Said two main parts are a cup l3which has a nipple [4' thereon adjacent the center and bottom of thecup, which nippleis' bored to provide a conduit l5 leading to the centerand bottom of said cup. The cup has a generally cylindrical shape and ofparticular significance is the inner cylindrical surface I6 whichextends for at least an inch and preferably slightly in excess of oneinch; for example, it may extend 1% inches.

Adjacent the right-hand edge of the cylindrical surface I6, as viewed inFig. 2, the cup I3 is provided with a peripheral internal groove l'1,adjacent and to the right of which it is threaded, as clearlyillustrated in the drawing. The cup is'aone-piecesolid member andwhich-has a corrtinuous cylindrical external surface I 9 generallycoextensive with, the cylindrical surface l 6 and which is,coextensivegtherewithifor at 1(- ast 1 inch andpreferablyffslightlyfin"excess thereof,

s c as i n s1- Th l g! ii f ls e eram p ovi with a circurnferential'groove 20which at least in part is iq p sit t $111 25 the; t grooves d2I!cooperating-toformywhat is in effect *a singlecircum'ferentialfgroove o "passageway*aroundfthe external periplieryofithe "plug l 8 '-andfthe 'irie ternal periphery of ihecup l3. ,Thebottom or left-hand end of the-plug l 8 a's-viewed' in "Fig. 2 of thedrawing, is spaced slightly from the bot tom of the cup 13, this spacingnot being particularly critical, though preferably slightly in excess ofthe spacing between the surfaces [6 and IS. The spacing between thesurfaces It and i9 is somewhat critical. It is preferably of the orderof .020 inch.

Adjacent its right-hand end, as viewed in Fig. 2 of the drawing, and atits center the plug l8 is provided with a conduit-forming opening Hwhich is preferably screw-threaded at 22 to receive a screw-threadedfitting whereby it may be attached to the housing ID or the like.Opening 2! extends into a central axial conduit leading to the interiorof the plug 18, from which there is a plurality of radial conduits 23extending to the groove 20, thus providing branch passageways from theopening 2| to the peripheral groove l'l20.

The plug I8 is also provided with a peripheral ledge 24 and with threadsto receive the threaded top of the cup I3. The ledge 24, of coursedetermines the final position of the plug l8 with respect to the cup l3,thus positioning the bottom of the plug l8 from the bottom of the cupl'3. If desired, a sealing wire 25 may lock the two principal parts ofthe arrester ll together, and a similar sealing wire 26 may look thearrester II to the housing I0.

As illustrated in Fig. l of the drawings, the two arresters H areconnected to the housing II) by virtue of fittings between said housingand the threaded openings 22. Air is fed to the nipple M of theright-hand flame arrester H, the left-hand flame arrester having itsconduit [5 in direct communication with the atmosphere. Air from a fanor blower is delivered by conduit l2 to the conduit or passageway l5 ofthe nipple M where it spreads through the area between the end of theplug l8 and the 13 receives a generally cylindrical plug 18 which bottomof the cup [3, flowing radially outward since they will take a reversepath from that just described for the incoming air, the flame arrestingtaking place principally as the hot gases pass between the surfaces [6and I9. Some arresting may take place between the end of the plug l8 andthe bottom of the cup l3, but this path is not particularly relied uponfor the flame arresting to function. Obviously; either" flame or air cantravel in either of the reverse directions through the flame arrester,and the function and operation will be the same in either case. As amatter of fact thenormal air flow will travel through theright-handflarne ar-' rester II in one direction jleading to thecontroller l0, and it will flow through the left-hand arrester II in arelatively reverse direction.

Obviously those skilled in the art may make various changes in thedetailsv and arrangement of parts without departing from the spiritandscope of the invention as defined by the claim hereto appended, and Ithereforewish not to be restricted to the precise construction hereindisclosed. U

Having thus described and shown an embodiment of my invention, what Idesire to secure by Letters Patent of the United States is:

A flame arrester for an electrical controller or the like comprising atwo piece device including a cup having a cylindrical inner surface anda, central conduit leading to the interior of said cup, a one-piece plugthreaded into said cup having a continuous outer cylindrical wall nearto but spaced slightly from said cylindrical inner surface and havingopposite closely adjacent surfaces about .020 inch apart and ex- Itending for at least 1 inch along the axis of said cylindrical surfaces,and conduit means extending first into the center of said plug thenradially thereof, said plug and cup cooperating to provide acircumferential groove adjacent the .ends of said radial conduitportions and at the periphery of said plug, the end of said plugadjacent said first mentioned conduit being spaced from the bottom ofsaid cup.

- SAMUEL H. YOST.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,499,461 Kruppa July 1, 1924FOREIGN PATENTS Number Country Date 132,793 Austria Apr. 10, 1933527,687 Germany June 20, 1931

